Sprint has posted a cool new advert this past weekend that advertises its 4G network with a little help from Apple’s iPhone. The commercial features two hip characters, the one with an iPhone conveniently named Steve and the other guy who breaks the ice by acknowledging that Steve’s iPhone is “cool.”

He then offers his friend a way to surf the web “up to ten times faster” than is possible on AT&T’s 3G network by utilizing the Overdrive, a $100 Sierra Wireless 3G/4G mobile hotspot that connects up to four WiFi devices to Sprint’s fourth-generation network. “While that happens,” Steve’s friend proclaims, “I’m gonna enjoy this tasty snack.” He then conveniently pulls out a red apple from his pocket and takes a bite while a full-screen video loads up instantly on Steve’s iPhone.

Currently available in over 25 markets and on select devices, Sprint’s 4G network delivers data at 6Mbps versus 3G’s average ranging between 600Kbps and 1.7Mbps. While Sprint’s marketing collateral says the Overdrive can “connect an iPhone to the Sprint 4G network to give it the advantages of 4G without switching carriers,” it never mentions the fine print. As you know, all iPhones sold in the US are tied to AT&T’s network. As a result, users pay at least $70 a month for the AT&T voice and data plan regardless of their use of rival services like Sprint’s Overdrive.

That said, those revved up to take advantage of Sprint’s Overdrive service won’t be able to escape their monthly AT&T service fees unless they purchase a 16GB/32GB iPhone 3GS as a no-commit $599/$699 option, respectively. However, many people (understandably) deem this too high a price to pay for the privilege of getting an iPhone without pledging themselves to a two-year AT&T agreement. Of course, there’s also a jailbreaking route that the vast majority of average users, let’s be honest, will avoid taking.